Currently, there are mainly two time measurement-based positioning methods: a time of arrival (TOA)-based positioning method and a time difference of arrival (TDOA)-based positioning method. The TOA-based positioning method needs to ensure strict synchronization not only between a to-be-positioned node and an anchor node but also between anchor nodes, while the TDOA-based positioning method needs to ensure strict synchronization only between anchor nodes. However, in many wireless networks, it is very difficult to achieve strict synchronization between anchor nodes. As a result, the TDOA-based positioning method cannot be used in an asynchronous environment.